Go Back   Home > Forums > Loudspeakers > Full Range

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 19th January 2005, 07:27 PM   #1
Nanook is offline Nanook  Canada
diyAudio Member
 
Nanook's Avatar
 
Join Date: Feb 2004
Location: Chinook Country.Alberta
Default zobel networks and imoedence reduction?

It seems to me that the bass output of full range drivers is seriously affected by the rising impedence as the driver reaches fs.

What can be done to reduce this rising impedence? A Zobel? Will this increase the output at or near fs? Has this been used in horns or other single driver, high efficiency speakers?

What are the other alternatives?

Any and all help appreciated as always.

stew
  Reply With Quote
Old 20th January 2005, 01:25 AM   #2
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
A "Zobel" will not generally increase the bass coming out of a
speaker. A current source or other high impedance amplifier
will increase the bottom end - if that's what you're looking for,
and in that case a resistor can be used to trim the damping of
the system.

Check out the article on www.firstwatt.com
  Reply With Quote
Old 20th January 2005, 01:30 AM   #3
rdf is offline rdf  Canada
diyAudio Member
 
rdf's Avatar
 
Join Date: Jun 2004
Location: big smoke
Assuming it's really a problem for the amp, the hard road is to add a tuned series LCR string in parallel with the woofer to flatten the peak. This is probably practical only for a driver/cabinet system with a single impedance rise. The double hump impedance curve of a bass relflex would make for some challenging optimization.
However, there's a much easier way to determine if it's worth pursuing: parallel the woofer with a resistor. 100 ohms in // will drop 8 ohms to 7.5 (miniscule) and a 50 ohm rise to 33 ohms (significant). Or, for full effect, test it using 12-15 ohms, which will drop the typical ~6 ohm mid-band impedance of a full range to 4 ohms and give it a whirl on the 4 ohm secondary taps. From the results decide if the full meal deal's worth the trouble.
  Reply With Quote
Old 20th January 2005, 01:59 AM   #4
diyAudio Member
 
Bill Fitzpatrick's Avatar
 
Join Date: Jun 2001
Location: Eugene, OR
Default Re: zobel networks and imoedence reduction?

Quote:
Originally posted by Nanook
It seems to me that the bass output of full range drivers is seriously affected by the rising impedence as the driver reaches fs.
It is not. Put the entire concern out of your mind and shift your focus elsewhere.
  Reply With Quote
Old 21st January 2005, 08:33 PM   #5
diyAudio Member
 
tenderland's Avatar
 
Join Date: Jul 2004
Location: us
Default full range

This link may provide some info
I am a nub my self and just completed a pair of full range speakers





http://www.quarter-wave.com/General/BSC_Sizing.pdf



Jeff
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Zobel networks Skeebopstop Class D 7 15th June 2009 07:04 AM
About snubbers(Zobel networks) CECCO Chip Amps 0 15th June 2008 09:40 AM
How do I parallel T networks? classd4sure Class D 25 5th October 2006 05:48 AM
building zobel networks zuki Parts 0 27th August 2006 05:52 AM
Biamping and Zobel Networks Won Multi-Way 22 5th December 2001 02:42 PM


New To Site? Need Help?

All times are GMT. The time now is 07:31 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2